<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <h1 id="myH1"></h1>
  <P id="myP"></P>
  <script>
    /*
    下面的这些代码会输出
    一个标题和一个段落
    并将代表主页的开始
    */
    document.getElementById("myH1").innerHTML = "Welcome to my Homepage";
    document.getElementById("myP").innerHTML = "This is my first paragraph.";
  </script>
  <p> <b>注释：</b>注释不会被执行。</p>
</body>
</html>